Visualizing Helical Wrapping of Semiconducting Single‐Walled Carbon Nanotubes by Surfactants and Their Impacts on Electronic Properties

Abstract

AbstractHelical wrapping of semiconducting single‐walled carbon nanotubes by surfactants has been considered as major driving forces for carbon nanotubes separation in aqueous solution using density gradient ultracentrifugation, gel chromatography, and aqueous two phase partition. The long‐time proposed helical wrapping of semiconducting SWCNTs by surfactants was visualized from AFM images showing the helical structures precisely oriented with respect to carbon nanotube axes. Helical wrapping of semiconducting SWCNTs by surfactants reduced the mobility by 10 times and negatively shifted voltage threshold (VT) for 6.2 V in semiconducting SWCNTs thin film transistors.